Having grown up around dogs, and now having two cats, I think a lot of people underestimate a cats intelligence because the cat is only interested in pleasing itself. I personally have cats who have figured out how simple mechanical devices like doors and drawers operate, and they have also figured out that I dislike them opening certain doors and drawers and they will get squirted by a spray bottle if they try (so they wait until I am asleep or away to misbehave).
Now, I'm not saying they're super smart creatures but they certainly have decent problem solving skills and an understanding of consequences at a fairly high level.
Beyond this I have seen my cats talk to each other using the same "phrase" to mean similar things in similar situations; and I'm curious whether the slight difference in meaning might actually be represented in a slight difference in the sound that is beyond my ability to hear. To explain what I mean, my cats may a "Birup" noise that seems to mean "Chase me" or "I'm Chasing You" when they play together.